1. Field of the Invention
The present invention relates to an IC card connector grounding structure suitable for use in a computer and others.
2. Related Art
Referring to FIGS. 8 and 9, a conventional IC card connector ground structure will be explained. An IC card connector 31 is comprised of a housing 33 made of an insulating material fitted with a plurality of pin terminals 32, and a shield cover 34 made of a metal plate attached on the upper surface of the housing 33.
The housing 33 has a stepped portion 33a provided on the corner portion of the upper surface, and a housing section 33b provided at front; in the housing 33 a pin terminal 32 is embedded, projecting out into the housing section 33b.
The shield cover 34 has a spring arm portion 34b provided at the center of the upper surface of the top plate section 34a, and a stepped portion 34c provided at the rear corner, formed one step lower than the top plate section 34a.
The shield cover 34 is attached on the upper surface of the housing 33, with the stepped portion 34c positioned at the stepped portion 33a of the housing 33, thus making up the IC card connector 31.
The IC card connector 31 stated above is mounted and used in an electronic apparatus such as a computer and others by mounting the IC card connector 31 on an electronic apparatus circuit board 35 on which an unillustrated circuit pattern is formed, and by screwing a nut 37 on a screw 36 after insertion of the screw 36 into the stepped portion 34c of the circuit board 35, the housing 33, and the shield cover 34.
Then, when the IC card connector 31 is mounted, the head of the screw 36 contacts the ground circuit pattern, and the shield cover 34 is grounded to the circuit pattern through the screw 36. The pin terminal 32 is in connection with the circuit pattern.
The IC card connector 31 stated above is so designed that an IC card 38 for use in communications and others through LAN and modem can be inserted and extracted. The IC card 38, when inserted into the IC card connector 31, is connected to the pin terminal 32 and attached with the pressure of the spring arm portion 34b as shown in FIG. 8.
The IC card connector 31 stated above is used for high-speed transmission in communications and others. Grounding the shield cover 34 to the circuit pattern is effected through the screw 36, which, however, generates an inductance component by the screw 36, producing noise during high-speed transmission and accordingly deteriorating the transmission performance.
The head of the screw 36 contacting the circuit pattern has little contact surface area, so that reliable grounding and good high-speed transmission characteristic can not be achieved.
In the conventional IC card connector grounding structure, the nut 37 is screwed on the screw 36 after insertion of the screw 36 into the circuit board 35, the housing 33, and the shield cover 34, and the shield cover 34 is grounded to the circuit pattern through the screw 36. The grounding structure, therefore, has such a problem that inductance component is generated by the screw 36, producing noise during high-speed transmission to thereby result in deteriorated transmission performance.
Since the head of the screw 36 contacts the circuit pattern as previously stated, there is little contact surface area, so that reliable grounding and good high-speed transmission characteristic can not be achieved.